RB30et Problem

[MadHatter]

Hello.
I did turbo conversion on my VL not long ago. It worked fine for a few months but now i have some weird problems.
Info: Running hi-flow turbo, no intercooler, and high compression.
It works fine when you start it.. and for a few mins after that, but if you thrash it for a while (say 10 mins) it all of a sudden just happens, it loses lots of power, wont rev past 3500rpm and when you pull over and idle it, it is very rough.. like lots of misses.
Sounds like moths being sucked thru the engine.

When i look at the spark plugs they are covered in black soot.. and if i clean them they become covered again in a 10 minute drive.. i dunno if thats normal or got anything to do with the problem i just thought it might be relevant.

Pleease help.

[NinetySix]

as in you bolted a high flow & manifolding onto a RB30E ? what ecu are you running?

[MadHatter]

The standard turbo ones, although i still have the N/A one in the garage if that helps.
Im also using the Turbo injectors and manifolds.

[NinetySix]

heard of very similar problems on S4 rx7 turbos, the computers are quite old by now and can prove very troublesom ...

why not upgrade to a replacement ecu, slap on a cooler and see if you cant get that CR down a bit

[guidos]

check afm, o2 sensor, and coolant temperature sensor.

by the sound of it, its running rich - i'd be thinking the AFM is at fault - clean the connector and check the wiring as a start, if you have a friend with a VL try borrowing his AFM to see if it makes a difference.

[MadHatter]

Yep its running rich.. veery rich.
I tried different afm's didnt seem to make a difference.
Would it be a good idea to crack open the AFM and just make it run a little leaner?

[guidos]

oh! check fuel pressure. forgot about that. i've heard that regulators ocassionally fail so badly the dump fuel straight into the plenum...